Auto-synchronous remote control apparatus with fine adjustment means



Jan. 10, 1950 M. N. YARDENY 2,493,844 AUTO-SYNCHRONOUS REMOTE CONTROL APPARATUS WITH FINE ADJUSTMENT MEANS Filed Nov. 27, 1945 McHL-L M Xmas/vy- INVENTOR Patented Jan. 10, 1950 AUTO-SYNCHRONOUS REMOTE CONTROL APPARATUS WITH FINE MEANS manor n. Yardeny, New York, N. Y. Application November 27, 1945, Serial No. 681..

1 This invention relates to a remote control device for positioning from a control point a load at a remote point to desired end positions and more particularly to the type in which the selective adjustment of the control device at the control point is coordinated with the position of the load at the remote point.

In a system of the type described there are possible only a limited number of coordinated load stopping positions. The object of the invention is to provide such a system with fine adjustment means which will permit the load to be moved to positions between the limited number of coordinated load stopping positions. An allied object is to provide a remote control system of the class described with fine adjustment means, as indicated above, which will make possible more precise positioning of the load.

For the attainment of the foregoing and such other objects as may appear or be pointed out herein, I have shown an embodiment of the invention in the accompanying drawing, wherein the single figure is a diagrammatic illustration of the improved remote control apparatus.

The remote control system according to this invention comprises a primary control device designated P. C. at the control point which is selectively adjusted to energize a reversible electric motor generally designated I at the remote point for placing a load L in desired positions. Additionally, the system includes means for coordinating a load L position at the remote point with the primary control device P. C. including a pilot motor generally designated 40 at the control point which is operatively connected as will be more fully described to the aforesaid primary control device P. C. and to a component of the coordinating means which controls the pilot motor and is designated P. M. 0.; the coordinating means further comprises component at the remote point which is in the nature of a commutating device designated C and is operatively connected as will .be more fully described with the load motor I. s .The primary control device 1?. C.,is selectively adjusted for positioning the load to desired positions which are limited in number to the "co- 5 Claims. (01.818 41) tion as part of the main system controlled by the primary control device P. 0.. the latter will'be .ilrst explained.

The primary control device P. C. comprises a pair of relatively movable members, one of which is insulated disc 2| rotatively mounted on a shaft 29 and carrying electrical conducting elements in the form of metal segments 22 and 23, the upper adjacent ends of which are separated by a gap 24. The other of the pair of members is a contact arm 25 secured to rotate with shaft 29 and provided with a distal contact 2| slidably engageable with the conducting segments 22, 23. The segments 22, 23 are connected to collector rings 26, 21, respectively, engaged by brushes 26*, 21 connected by transmission wires l6, I! to the reversing field windings i, 1 of the aforesaid load motor I at the remote point. Contact arm 25 of the primary control device P. C. is connected by lead 20 to a supply wire Ill leading from a switch its to terminal I! of a source of current supply "I at the control point. The common tap of reversing field windings 6, I, is connected by a lead 6| to the coils ll of a solenoid associated with the fine adjustment F. A. (and more particularly described subsequently) and thence by a lead 62 of a supply wire is leading through a switch its to the other terminal ll of the current source IO.

Contact arm 25 is selectively turned either clockwise or counter-clockwise, depending upon the direction in which it is desired to rotate load motor I, to engage either segment 23 to energize field winding 1 for clockwise rotation of motor I or segment 22 to energize the other winding 6 for counter-clockwise rotation. The circuit to the field windings is readily traced from one supply terminal it, closed switch its, leads ll,

-20, to contact arm 25, the engaged segment 23 ordinated motor stopping positions of the prior 22 and via one of the transmission wires l0, H to the corresponding field winding 6, I, returning via common lead 60, solenoid coil 6|, lead 82 of the other supply wire l2. closed switch its, and supply terminal IS. A pointer 15 is secured to rotate with shaft 29 to indicate load positions on a stationary circular scale ll. Motor shaft 2 is connected through gears 3 to the load L.

Contact arm 25 is turned in the desired direction to an extent, as indicated by pointer Ii in scale It, required to cause rotation of the load motor to move to the desired end positions.

Load motor I continued to rotate, in the desired direction, until gap 24 of insulated disc 2| is again brought into alignment with contact arm 25 or, rather, its contact 28. For this purinsulated disc 2| is rotated, in a direction a ifnable gap 24 to overtake the contact arm 25, by a pilot motor 40 associated with the aforementioned pilot motor control device P. M. 0. Pilot motor 40 is operatively connected to turn insulated disc 2| of the primary control P. C. by its shaft 4| and a pinion 42 secured thereon meshing with a gear zlg secured to rotate with insulated disc 2|.

Pilot motor 40, in addition to its function in rotating disc 2| (as just explained), also functions in coordinating instriunentalities of the pilot motor control P. M. C. for causing load motor to stop in a position corresponding to the adiusted position of contact arm 25 of the primary control P. C. which will now be described. The pilot motor control P. M. C. comprises an insulated disc 36 rotatively mounted on a shaft 31 and provided with a gear 369 secured to rotate therewith which meshes with a pinion 43 secured on pilot motor shaft 4|. A pair of conducting segments 34. are mounted on insulated disc 36, the adjacent upper ends of which are separated by a gap.33, the lower adjacent ends being separated by a gap 33'. concentrically disposed about shaft 31 and adapted to slidably engage the segments 34, 35 are a plurality of spaced contacts 3|, 32 and others not designated; contacts 3|, 32, etc. are narrower than the gaps 33, 33' which separate the adjacent ends of the segments. Segments 34, 35 are connected to collector rings 33. 33, respectively, engaged by brushes 33*, 33* which are connected by leads 33', 39' to reversing field windings 44 and 45, respectively, of pilot motor 40.

Stationary contacts 3|, 32, etc. of the pilot motor control device P. M. C. are individually connected by wires l3 to corresponding contacts 5|, 52, etc. of the aforementioned commutating device at the remote point generally designated C in the drawing. Stationary commutator contacts 5|, 52, etc. are slidably engaged by a rotatable contactor 56, or rather by a contact element 56 at its distal end. Commutator arm is secured to a shaft 50, to which is also secured a gear 56g meshing with a pinion 5 secured on shaft 2 of load motor I. commutator arm 56 is connected by a lead 59 to the aforementioned transmission wire l9 leading back to terminal l9 of the current source ID at the control point.

It has already been explained that the displacement of contact arm 25 of the primary control device at the control point either to the left or right of its normal position (as shown)-in which its contact 28 is at gap 24 between conducting segments 22, 23-will cause load motor I to rotate in the desired direction. Rotation oi motor I will cause a concurrent turning of commutator arm 56, which is instrumental in causing a coordinated turning of pilot motor 40, in the following manner: When arm 56 of the com mutator C is in a position with its contact 5|; engaging stationary contact 5|, disc 36 of the pilot motor control device P. M. C. being at its corresponding coordinated position with contact 3| (which corresponds to stationary contact 5| of the commutator) at gap 33, the circuit interconnecting commutating device 0 at the remote point and the pilot motor control device P. M. C. at the control point is broken at contact 3l-gay 33 of the P. M. C. device. This circuit may be traced from supply terminal I9 at the control point, through transmission wire l9 and lead 59 to rotatable arm 56 of the commutator C at the remote point, its contact 56*, to stationary contact 5|, returning via the respective one of the inter-connecting wires l3 to the corresponding stationary contact 3| of the pilot motor control device at the control point. In the position mentioned above, the circuit is broken since the energized contact 3| is at gap 33 of insulated disc 36. The. circuit to the reversing field winding 44 or 45 of pilot motor 40 is thus broken and the motor is stopped. But as load motor continues its rotation (by reason of the engagement of contact arm 25 of the primary control device with one or the other of the segments 22, 23, as explained above), arm 56 of commutator C continues to tum-say, in a clockwise directionand its contact 56 engages the next commutator contact, which is 52. The corresponding contact 32 of the pilot motor control device is now energized and,

by reason of the fact that it engages segment 35, the circuit to the respective reversing field winding 44 or 45 of pilot motor 40 associated with the particular engaged segment 34, 35 will be completed. The tracing of the circuit may be continued from energized contact 32, engaged segment 35, its collector ring 39 and brush 39*, lead 33 to field winding 45 and from the common tap of the windings via short lead |2 to supply wire l8 leading to the other supply terminal I8 The resulting rotation of pilot motor 40 causes a concurrent turning of both insulated disc 2| of the primary control device and insulated disc 36 of the pilot motor control device. Disc 2| is turned in direction to cause gap 24 to overtake the displaced contact arm 25 and to cause its contact 23 to be free of both segments 22 and 23, thus breaking the circuit to the field winding 6 or i, and thereby bringing load motor to a stop. Disc 36 of the pilot motor control device is likewise turned in a direction to cause gap 33 to reach stationary brush 32 (which is in energized condition, as described above, by reason of the engagement of commutator contact arm 56 with the corresponding stationary contact 52). The stationary contacts 3|, 32, etc. being narrower than gap 33, the arrival of the gap at energized contact 32 will break the circuit to field winding 45, thus bringing pilot motor 40 to a stop.

The turning of commutator arm 56, by load motor I, to bring its contact 56 into engagement with successive ones of the stationary c0ntacts 5|, 52, etc., will cause a coordinated turning of pilot motor control disc 36, by its energization of pilot motor 40, gap 33 reaching the energized one of the contacts 3|, 32, etc., corresponding to the engaged commutator contacts 5|, 52, etc., to break the current supply to the pilot motor. Concurrently the pilot motor rotates insulated disc 2| of the primary control device to bring gap 24 progressively nearer to the contact arm 25 in its advanced position to which it had been selectively adjusted. Current is continued to be supplied to the load motor I, thus causing commutator. arm 56 to continue to turn and engage successive commutator contacts 5|, 52, etc. This stepped advance of commutator arm 56 and pilot motor control disc 36 will continue until gap 24 of the primary control disc 2| reaches the contact arm 25, at which time the load motor will be stopped in the desired end position; the commutator arm 56 will be stopped at its last engaged commutator contact 5| 52, etc. and pilot motor control disc 36 will be stopped with the last corresponding contact 3|, 32, etc. at gap 33 separating the segments 34, 35.

It is thus seen that there is presented in the drawing a remote control system in which a primary control device P. C. at the control point, which comprises a rotatable disc 2| having a pair or electrical conducting segments 22, 23 separated by a gap 24, and a selectively adjusted contact arm iii engageable with the segments,

initiates the rotation oi a motor I in the de sired direction to move a load at the remote point,

its gap 24 overtakes and reaches contact arm 25 in its adjusted position, whereat current to the remote motor is cut-off. The aforesaid instrumentalities for turning the primary control disc ii in strict accordance with load movement include a commutator device C having a plurality of contacts 52, etc. engageable by an arm 56 driven from the load motor, and a pilot motor 56 for driving the primary control disc 2| under control of a device-the pilot motor control device P. M. C.--having a plurality of contacts 3|, 32, etc. connected to corresponding contacts of the commutator C at the remote point, and a disc 36 provided with a pair 01' segments 34, 35 separated by a gap 33 engageable with contacts II, 32, etc.

Commutator arm 58, driven by the load motor at the remote point, and the pilot motor control disc 35, driven by the pilot motor 40 at the control point, both turn substantially synchronously in that the disc 36 is turned by the pilot motor to present its gap 33 at that one of thecontact 3i, 32, etc. which spatially corresponds to, and is energized by, the particular commutator contact 5!, 52, etc. simultaneously engaged by the commutator arm 56. In this position 01' the pilot motor control disc with gap 33 at an energized contact 3 i, 32, etc, the current supply to the pilot motor is shut off, to stop the pilot motor and consequently the turning 01' primary control disc II. It is thus seen that the pilot motor rotates in steps, from one pilot motor contact (and commutator contact) to the next, and that primary control disc 2! is likewise turned in a stepped advance (as does the pilot motor control disc 38) from the foregoing it follows that the accuracy of positioning the load by the device is determined to a great extent (among other conditions) by the extent oi the possible angular movement of contact 58 while in engagement with one of the contacts Si, 82, etc., corresponding to the stopping position of P. M. C. and P. C. For certain applications it may be desirable, however, to position the load more precisely than is possible with the device of this type, as, for instance, when it is used with radio apparatus.

The fine adjustment device 1". A. comprises a pair oi rotatably movable members, one of which is an insulated disc 03 rotatably mounted about a shaft 84 and provided with two contacts 83, 1 which are connected to respective collector rings 68, 89 which are engaged by contact brushes it, 69*, respectively which are connected by leads 68', 69' to, respectively, the aforementioned leads l6, IT. The proximal end of a contact arm II is connected by a lead II to the aforementioned supply wire it. The contact arm is secured to rotate with shaft 84 and provided at its distal end with a contact engageable with the contacts 88, 81 of the insulated disc ll. Contact arm I. is

moved, by a manipulative knob (not shown), to engage either the contact I or'the contact 81.

Engagement with contact 88 will complete a circuit to energize ileld winding 6 oi load motor I, which circuit may be traced from one supply wire I9, lead II, to contact arm II, engaged contact 68, collector ring 83, brush it, and through lead 83', to the lead I! connected to the outer terminal of field winding 8 from the inner terminal of which the circuit continues through lead 60, solenoid coil 8| and lead 62 to the other supply wire l8.

On the other hand, engagement of contact 10* of contact arm 10 with the other contact 81 is effective to energize the other field winding I for clockwise motor rotation. winding 6 causes rotation of the load motor in a counter-clockwise direction, the circuit to which is quite similar to the one just traced to field winding 8. The fine adjustment device F; A. is designed for very small stepped movement for which reason it is implemented. with means for quickly breaking the engagement between either contact 10* and contact 66 (counter-clockwise load movement) or between contact 10 and contact El (for clockwise load rotation) This means includes a pair of spring blades 18, 19 secured to the insulated disc 53 with their distal ends in spring engagement with opposite sides of the contact arm ill to maintain the latter in centered position. The insulated disc 53 is held by braking element 83 which is provided at the end of the solenoid armature the latter is provided with a collarBl between which and a fixed part of the frame 9 is interposed a compression coil spring 8 which tends to urge the brake element toward the disc 63.

By reason of the fact, as just described, that the insulated disc 63 is normally held stationary by the spring urged braking element 83, the contact arm 10 may be moved in either direction, depending upon the desired direction of load movement, by manipulation of its knob. Manipulative movement of contact arm 10 will tension the oneor the other spring blade, depending upon the direction of the manipulation engagement with one of the other of the contacts 86, 81. In addition to causing rotation of the load motor in the desired direction as already described, engagement of contact 10* with contact 66 or 61 will also energize solenoid 61 to counter-act the braking urgency of compression spring 8, with the the result that the braking element 83 is moved away from engagement with the insulated disc 63, permitting the disc to be moved by the tension imparted to one or the other of the spring blades 18, 19; For example, if the control arm 10 had been moved in a clockwise direction, as shown in the drawing, to engage contact 66 (to cause a load movement in a counter-clockwise direction) this would cause tensioning of the anterior spring blade I3, which is possible by reason of the fact,

as already explained, that stationary disc 63 is held stationary by brake element 83. Now, upon the removal of the brake element 83 on energization of solenoid 6|, insulated disc will be free to move and will move in a clockwise directionwhich is the same direction in which the contact arm 10 had been moved-by the tension spring blade l8,'the proximal end of which being secured on the disc, the latter is free to move in that direction, its distal end reacting against the contact arm Ill which is'held stationary by the hand of the operator. In a similar manner, manipulation of contact arm Ill in the opposite or counter- Energization of field clockwise direction will, by tensioning the armature spring blade 19, cause a movement of the insulated disc 63 in the same counter-clockwise direction to break engagement between contact and contact 61.

It will be understood, of course, that the line adjustment device F. A. is manipulated for more precise positioning of the load at a time when the primary control device P. C. is in a normal inoperative position with its contact arm at the gap 24, so that the circuits from the primary control P. C. to the motor windings are broken at that point. It will be further seen that the fine adjustment F. A. is so designed that the stepped impulses given by it to the load motor will be of very minute degree so that the load may be brought to the precise desired position within the range of possible motor-stopping positions, mentioned above, to which the load had been moved by the primary control device P. C. and

the cooperative commutator C and pilot motor control devices P. M. C. The fine adjustment device F. A. may be connected to the indicator ll, l5 at the control point by a shaft 64 and gears 64g, l5y, with a suitable gear ratio to indicate thereon the additional movement imparted by it to the load.

The accuracy or preciseness of the positioning of load L in response to the selective adjustment of the primary control device P. C. will depend upon the said stepped advanced imparted to the pilot motor device P. M. C. and the primary control P. C., and, more particularly, upon the limit of accuracy of such stepped advances as established at the commutator C. Referring to the drawing, it will be seen that electrical contact will be made between the distal contact 56* of commutator arm 56 and a stationary contact 5|, 52, etc. so long as there is physical engagement between any portion of distal contact 56 and any portion of the stationary contact 5 l, 52, etc. That is, the distal contact 5'6 need not be exactly centered at contact 52 (as shown in the drawing) in order to complete the circuit to energize the corresponding one of the contacts 3|, 32, etc. at the pilot motor control device P. M. C. The extreme positions of commutator arm 56 within which its distal contact 56* makes electrical contact with a stationary contact; 5|, 52, etc., define a range of possible stopping positions. Hence, it will be seen that the limit of accuracy of the stepped advance will depend, besides any loose play in the system, upon the said range of possible stopping positions of commutator C.

It will be understood that various features and principles of each embodiment of the invention above described or referred to may be utilized or substituted in other embodiments.

While the invention has been described in detail with respect to certain particular preferred examples, it will be understood by those skilled in the art after understanding the invention that various changes and further modifications may be made and parts of the improvements may be used without others, without departing from the spirit and scope of the invention, and therefore it is intended in the appended claims to cover all such changes and modifications.

I claim:

1. A control apparatus for controlling a motor having reversing field windings and connected with a load at a remote point for placing the load in any desired position, comprising a pair of control elements at a control point, one of the elements comprising a pair of electrically conducting members connected in a circuit with the respective motor windings and separated by a gap, the other element comprising a contact arm for engaging the conducting members, a pilot motor for moving one of the elements, the other element being movable by other means for directional control of the motor corresponding to the engaged conducting member and for deenergizing the motor in response to the contact arm reaching the gap; means to control the pilot,

motor rotation by theload motor in steps of predetermined length ;for coordinating the load position with the position of the control element movable by other means; a supplementary pair of control elements at the control point, one of the saidsupplementarycontrol elements comprising a pair of spaced contacts connected in circuit with the respective load motor windings, the other supplementary control element comprising a manually operable contact arm capable of engaging one or the other of said contacts; and means to normally urge the contact arm into a disengaged position, said disengaging means being rendered operative for the purposes aforesaid by an engagement between the contact arm and one of the contacts for limiting the current supply to the load motor to short impulses, thereby causing the load motor to be rotated in short steps' until the desired load position between two successive steps is reached.

2. A control apparatus for controlling a motor having reversing -field windings and connected with a load at a remote point for placing the load inany desired position, comprising a pair of control elements at a control point, one of the elements comprising a pair of electrically conducting members connected in a circuit with the respective motor windings and separated by a gap, the other element comprising a contact arm for engaging the conducting members, a pilot motor for moving one of the elements, the other element being movable by other means for directional control of the motor corresponding to the engaged conducting member and for deenergizing the motor in response to the contact arm reaching the gap; means to control the pilot motor rotation by the load motor in steps of predetermined length for coordinating the load position with the position of the control element movable by other means; a supplementary pair of control elements at the control point, one of the said control elements comprising a pair of spaced contacts con-- nected in circuit with the respective load motor windings, the other control element comprising a manually operable contact arm capable of engaging one or the other of said contacts; means to normally urge the contact arm into a disengaged position, said disengaging means being rendered operative for the purposes aforesaid by an engagement between the contact arm and one of the contacts for limiting the current supply to the motor to short impulses, thereby causing the motor to be rotated in short steps until the desired load position between two successive steps is reached; and means for rendering the supplementary control elements operative for the purposes aforesaid when the contact arm of the first pair of control elements reaches the gap.

3. A control apparatus for controlling a motor connected with aload at a remote point for placing the load in any desired position, comprising a pair of control elements at a control point, one element comprising a pair of conducting members separated by a neutral point, the other element comprising a contact arm for engaging the conducting members; circuit means including the control elements and the load motor for controlling directional rotation of the motor by the position of the contact arm on one or the other of the conducting members and for stopping the motor when the contact arm is aligned with the neutral point; a pilot motor at the control point operatively connected with one of the control elements, the other control elements being manually movable; a second pair or control elements at the control point, one element of the second pair comprising a pair of conducting members separated by a neutral point, the other element of the second pair comprising a plurality of contacts forengaging the conducting members, the

conducting members being connected in a circuit with the pilot motor; means operated by the load motor for successively energizing the contacts of the second pair of control elements, thereby causing the pilot motor to advance the corresponding control element of the first pair in steps of predetermined length until the last named control element reaches a position in which the respective neutral point registers with the contact arm, thereby stopping the load motor; and a third pair of control elements at the control point, one element of the third pair being operatively connected with the load motor, the other element of the third pair being manually operable, one element of the third pair comprising a pair of contacts connected in a circuit with the load motor independently of the first pair of control elements, the other element of the third pair comprising a contact arm for engaging the contacts, the third pair of the controlelements being thereby adapted to control the load motor rotation after the last step of the coordinated movement of the load.

4. In a control apparatus for placing a load at a remote point in any desired position, the combination, with a motor connected with the load, of a pair of control elements at a control point, one of said control elements comprising a contact connected in circuit with said motor, the other control element comprising a contact arm capable of engaging said contact for closing an energizing circuit for said motor, means including a normally inoperative mechanism opposing but normally ineffective to prevent relative discuit, whereby the motor is energized for a brief period only upon each relative displacement of the control elements.

5. In a control apparatus for placing a load at a remote point in any desired position, the combination, with a reversible motor connected with the load, of a pair of control elements at a control point, one of said control elements comprising a pair of relatively fixed contacts connected in circuit with said motor, the other control ele- .ment comprising a third contact movable relative to said fixed contacts and capable of selectively engaging either of said fixed contacts for closing a respective energizing circuit for said motor so as to rotate the motor in a respective sense, a first movable member supporting said fixed contacts, a second movable member supporting said third contact, spring means tending to maintain said movable members in such relative position as to maintain the third contact disengaged from said fixed contacts, mechanism normally immobilizing one of said movable members, thereby rendering said spring means ineflective to prevent relative displacement of said fixed and third contacts upon movement of the other of said movable members, and circuit means responsive to closure of either of said energizing circuits for operating said mechanism so as to free said one movable member to follow any displacement of said other movable member and restore said contacts to disengaged position, thereby de-energizing the motor.

MICHEL N. YARDENY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 714,862 Buck Dec. 2, 1902 1,693,314 Murphy Nov. 27, 1928 1,979,588 Vreeland Nov. 6, 1934 2,334,967 Thomas et al. Nov. 23, 1943 

